Ford Festiva. Manual — part 45

continuity exists, go to next step.

2. Install BOB. Connect ECT. Warm engine to normal operating temperature. Measure resistance between ECT test pin and SIGRTN pins.

If resistance is 500-1000 ohms, replace ECA. If resistance is not 500-1000 ohms, replace ECT sensor.

PINPOINT TEST VAT - VANE AIR TEMPERATURE SENSOR

Fig. 10: Identifying VAT Circuits

VAT CIRCUIT PIN IDENTIFICATION

1. Turn ignition off. Ensure engine is at operating temperature. With ignition off, install BOB. Turn ignition on. Measure temperature near

VAT sensor. Measure voltage between VAT and SIGRTN test pins. Compare voltage to specifications shown in

VAT SENSOR

VOLTAGE

table. If voltage is within specification, VAT circuit is okay. If voltage is not within specification, go to next step.

VAT SENSOR VOLTAGE

2. Turn ignition off. Disconnect ECA. Measure resistance between VAT and SIGRTN test pins. Measure temperature near VAF meter.

Compare resistance to specifications shown in

VAT SENSOR RESISTANCE

table. If resistance is within specification, go to next

step. If resistance is not within specification, go to step 4).

3. Unplug VAF sensor connector. Measure resistance between VAT test pin and all other test pins. If any resistance is less than 5 ohms,

repair VAT wire from ECA to VAF meter. If all measurements are greater than 5 ohms, replace ECA.

4. Turn ignition off. Unplug VAF meter connector. Monitor temperature near VAT sensor. Measure resistance between VAF meter VAT

and SIGRTN terminals. Compare resistance to specifications shown in

VAT SENSOR RESISTANCE

table while heating VAT sensor .

If resistance is within specification, repair VAT and/or SIGRTN wires from VAF to ECA. If resistance is not within specification, replace
VAF meter.

VAT SENSOR RESISTANCE

NOTE:

Enter this test only when a Code 10 is displayed during QUICK TESTS procedure or when directed here
from another PINPOINT TEST. Ambient temperature must be higher than 50°F (10°C) for this test.

Circuit

ECA Pin

BOB Pin

Wire Color

1.3L

GND

2A

46, 49

BLK

VAT

2P

45

GRN/BLK

1.6L

SIGRTN

2C

46,49

BLU/YEL

VAT

2J

25

BRN/YEL

Temperature °F (°C)

(1)

Volts

20 (-6)

3.64

30 (-1)

3.36

40 (4)

3.05

44 (7)

2.79

50 (10)

2.29

60 (16)

2.61

70 (21)

2.35

80 (27)

2.05

90 (32)

1.76

100 (38)

1.57

(1)

Values may vary by 15 percent.

PINPOINT TEST TP - THROTTLE POSITION SENSOR

Fig. 11: Identifying TP Circuits

TP CIRCUIT PIN IDENTIFICATION

1.6L

1. Turn ignition off. Install BOB. Turn ignition on. Measure voltage between BOB test pins TP and SIGRTN while opening throttle.

Compare voltage to specification in

TP SENSOR OUTPUT VOLTAGE

table. Go to next step if output voltage is not within

specification.

TP SENSOR OUTPUT VOLTAGE

2. Turn ignition off. Unplug TP sensor connector at throttle body. Using jumper wires, connect VREF and SIGRTN wires on harness

Temperature °F (°C)

Ohms

-4 (-23)

15,000

32 (0)

5210

68 (20)

2500

104 (40)

1100

140 (60)

600

176 (80)

300

NOTE:

Enter this test only when a Code 12 is displayed during QUICK TESTS procedure or when directed here
from another PINPOINT TEST.

Circuit

ECA Pin

BOB Pin

Wire Color

1.6L

IDL

1E

28

GRN/ORG

SIGRTN

2C

46, 49

BLK/YEL

TP

2G

47

ORG

VREF

2A

26

WHT/BLK

Throttle Opening

(1)

Voltage

1/8

1.00

1/4

1.60

3/8

2.37

1/2

2.74

5/8

3.15

3/4

3.43

7/8

3.60

(1)

Voltage may vary by 15 percent.

connector to corresponding terminals on TP sensor connector. Turn ignition on. Measure voltage between TP and SIGRTN terminals on
TP sensor while opening throttle. Compare voltage to specification in

TP SENSOR OUTPUT VOLTAGE

table. If voltage is within

specification, repair TP wire to ECA. Go to next step if voltage is not within specification.

3. Turn ignition off. Unplug TP harness connector. Turn ignition on. Measure voltage between VREF and SIGRTN wires on TP harness

connect-or. If voltage is 4-5 volts, replace TP sensor. If voltage is not 4.5-5.5 volts, go to next step.

4. Measure voltage between VREF wire on TP harness connector and ground. If voltage is 4-5 volts, adjust or replace throttle position

sensor. If voltage is not 4-5 volts, go to

PINPOINT TEST VREF

.

PINPOINT TEST BP - BAROMETRIC PRESSURE SENSOR

Fig. 12: Identifying BP Sensor Circuits

1.3L

BP sensor is incorporated into ECA; it cannot be checked or serviced separately. If Code 14 is set and cannot be cleared, replace ECA.

1.6L

Turn ignition off. Connect BOB. Remove dust cover from BP sensor, located on passenger side cowl. Turn ignition on. Connect vacuum pump
to BP sensor. Measure voltage between pins BP and SIGRTN on BOB while applying vacuum to BP sensor. See

BAROMETRIC

PRESSURE SENSOR OUTPUT VOLTAGE

table. Replace BP sensor if voltage is not as specified.

BAROMETRIC PRESSURE SENSOR OUTPUT VOLTAGE

PINPOINT TEST EGO - EXHAUST GAS OXYGEN SENSOR

EGO CIRCUIT PIN IDENTIFICATION

1. Warm engine to operating temperature, and let idle. Unplug EGO sensor. Measure voltage between EGO sensor connector (sensor side)

NOTE:

Enter this procedure only when a Code 14 is displayed during QUICK TESTS procedure or when
directed here from another PINPOINT TEST. To prevent unnecessary replacement of components, note
following non-EEC items may be at fault: unusually high or low atmospheric pressure, blocked vacuum
lines, or basic mechanical engine components.

Vacuum (In. Hg.)

(1)

Voltage

0

3.84

5

3.36

10

2.66

15

1.93

20

1.26

25

.58

(1)

Voltage may vary by 15 percent.

NOTE:

Enter this test only when a Code 15 (lean) or Code 17 (rich) is displayed during QUICK TESTS
procedure.

Circuit

ECA Pin

BOB Pin

Wire Color

EGO

1.3L

2N

29

BLU

1.6L

2D

29

BLK

and ground. With engine at idle, voltage should fluctuate between 0.2-0.8 volt.

2. Increase and decrease engine speed while reading voltmeter. When engine speed is decreasing, voltage should decrease. When engine

speed is increasing, voltage should increase. If voltage is within specification, go to next step. If voltage is not within specification,
replace EGO sensor.

3. With ignition off, install BOB. Leave ECA disconnected. Unplug EGO sensor connector. Measure continuity between EGO test pin and

EGO sensor connector wire. If continuity exists, EGO circuit is okay; return to QUICK TESTS if sent here from there. If not sent here
from QUICK TESTS, replace ECA. If voltage is not as specified, repair VMREF wire to VAF. If continuity does not exist, service EGO
sensor wire to ECA.

PINPOINT TEST PRC - FUEL PRESSURE REGULATOR CONTROL SOLENOID

Fig. 13: Identifying PRC Circuit & Connector

PRC CIRCUIT PIN IDENTIFICATION

1. Locate Fuel Pressure Control (PRC) solenoid on cowl panel, next to canister purge solenoid. Unplug PRC solenoid connector. Remove

both vacuum lines. Plug vacuum port from engine vacuum source. Apply vacuum to remaining port. Replace PRC solenoid if it does not
hold vacuum.

2. Turn ignition off. Connect BOB. Leave ECA disconnected. Reconnect wiring to PRC solenoid. Turn ignition on. Apply vacuum to PRC

solenoid. Connect jumper wire between PRC test pin on BOB and ground. If vacuum drops to zero, PRC solenoid function is okay.
Return to QUICK TESTS if sent here from there. If vacuum does not drop to zero, go to next step.

3. Turn ignition off. Unplug PRC solenoid connector. Turn ignition on. Measure voltage between VPWR wire on harness connector and

ground. If voltage is not higher than 10 volts, repair VPWR wire to main relay. If voltage is higher than 10 volts, go to next step.

4. Turn ignition off. Unplug PRC solenoid connector. Turn ignition on. Measure voltage between solenoid connector VPWR wire and

solenoid connector SIG wire. Connect jumper wire between PRC test pin on BOB and ground. If voltage is higher than 10 volts only
when solenoid is activated, replace solenoid. If voltage is not higher than 10 volts only when solenoid is activated, go to next step.

5. Turn ignition off. Connect BOB. Leave ECA disconnected. Unplug solenoid connector. Measure resistance between SIG test pin and

solenoid connector SIG wire. If resistance is not less than 5 ohms, repair SIG wire to ECA. If resistance is less than 5 ohms, go to next
step.

6. Turn ignition off. Connect BOB. Leave ECA disconnected. Unplug solenoid connector. Measure resistance between SIG test pin and all

other test pins. If resistance between SIG PRC test pin and any other pin is less than 5 ohms, repair PRC wire to ECA. If resistance
between PRC test pin and any other pin is greater than 10,000 ohms, replace ECA.

PINPOINT TEST CANP - CANISTER PURGE CONTROL SOLENOID

NOTE:

Enter this test only when a Code 25 is displayed during QUICK TESTS procedure or when directed here
from another PINPOINT TEST.

Circuit

ECA Pin

BOB Pin

Wire Color

PRC (1.6L)

2K

31

BRN

NOTE:

Enter this test only when a Code 26 is displayed during QUICK TESTS procedure or when directed here
from another PINPOINT TEST.